1. Field of the Invention
The present invention relates to a surveillance system, surveillance terminals, and a surveillance center, the surveillance system being configured to detect a hazard such as crime, calamities, etc. and alert residents to the hazard in the locality of the hazard and its vicinity, and the invention relates to a hazard and alert signaling method.
2. Description of the Related Art
In a prior art surveillance system built by networking a surveillance center and a plurality of surveillance terminals, the surveillance center performs the surveillance control, using discrete links to each surveillance terminal. For example, when a surveillance terminal detects a hazard, the surveillance center obtains information in various aspects of the hazard from only the surveillance terminal that has just detected the hazard and performs the surveillance and alert task, based on the obtained information (for example, refer to Kokai, Japanese Unexamined Patent Publication No. 2000-316146).
In another similar system of prior art, when a hazard occurs in one of a plurality of homes existing in one area, the home security communications device provided in that home outputs a hazard detection signal and this signal is sent over a wireless channel via a communication managing unit in the area to the surveillance center. The surveillance center signals a hazard alert to mobile phones carried by residents of the above home and also signals the alert to the hazard occurred in the one home to other homes within the same area (for example, refer to Kokai, Japanese Unexamined Patent Publication No. 2002-271522).